News

Bonds from the Carlsbad Desalination Plant and pipeline were upgraded to BBB and given a stable outlook in a new report from Fitch Ratings. The rating upgrade affirms the project’s sound management and its ability to provide a stable, reliable source of drinking water to the San Diego region.

“Desalinated water, as regulated by the permit for Poseidon, is an important component of our overall water supply portfolio,” said San Diego Water Board chair Henry Abarbanel.The updates are expected to increase the facility’s drinking water production from 54 to 60 million gallons per day, a significant boost in light of the region’s arid climate and inevitability of droughts. The renewed permit supports the use of ocean water as a reliable supplement to traditional water supplies and features a number of environmental protections adopted by the State Water Board in its Desalination Amendment in May 2015. California is a world leader in desalination permitting and environmental protection.

Located 30 miles north of San Diego on the shores of the Agua Hedionda Lagoon, the Carlsbad plant is the largest and most technologically advanced seawater desalination project in the Western Hemisphere. The project relies on reverse osmosis, a filtering process that separates salt from seawater and eliminates impurities such as bacteria and viruses. Approximately 100 million gallons per day of ocean water from the adjacent lagoon enters the plant through a 72-inch pipe, then cycles through a multi-layer tank that uses sand, gravel and anthracite to remove algae and other large impurities. Then, a reverse osmosis cycle removes the salt. Once the filtering is complete, the potable water is disinfected with chlorine and pumped to retailers throughout the county. The brine that remains is diluted with seawater and returned to the ocean.

While Carlsbad is one of 12 existing desalination plants in California - a state that more heavily relies on conservation, recycling, stormwater capture and groundwater recharge for its water supply - ocean filtration systems operate in more than 120 countries and are considered a vital water source alternative in many regions, particularly the Middle East, the Mediterranean and the Caribbean.